To save money, many business enterprises implement some sort of authorization system to control and/or restrict the placement of telephone calls by their employees. For example, forced authorization codes (FACs), which require a caller to enter a valid authorization code prior to extending calls to classes of dialed number, are commonly used in private branch exchange (PBX) systems to regulate the types of calls that certain users can place (e.g., international calls and external toll calls). In such a system, a user placing a call needs to enter a valid FAC code in order for the call to be extended beyond the PBX. Modern PBX systems typically implement this feature by having an administrator set the FAC codes in the system, and then distribute these codes to selected users that have a legitimate business need to place an international or toll call.
One problem with the FAC approach to regulating toll calls is that the authorization rights are statically assigned to users, which, often times, is counter productive. For example, in a large organization or enterprise a number of employees normally have no need to place long distance or international calls as part of their normal work. The system administrator may therefore block or restrict their ability to place these types of calls. Occasionally, however, a blocked employee may need to place such a call in the course of performing their work duties. In such cases, the use of statically assigned FACs does not work very well. That is, the FAC feature in existing PBX systems lacks the flexibility to allow a normally restricted employee (one without access to a valid FAC) to place certain international or toll calls in special situations.